Due to age, high cholesterol and other contributing factors, a large percentage of the population has arterial atherosclerosis that totally occludes portions of the patient's vasculature and presents significant risk to the patient's health. For example, in the case of a chronic total occlusion (CTO) of a coronary artery, the result may be painful angina, loss of functional cardiac tissue or death. In another example, complete occlusion of the femoral or popliteal arteries in the leg may result in limb threatening ischemia and limb amputation.
Commonly known endovascular devices and techniques for the treatment of chronic total occlusions (CTOs) are either inefficient (resulting in a time consuming procedure), have a high risk of perforating a vessel (resulting in an unsafe procedure), or fail to cross the occlusion (resulting in poor efficacy). Physicians currently have difficulty visualizing the native vessel lumen, cannot accurately direct endovascular devices toward the visualized lumen, or fail to advance devices through the occlusion. Bypass surgery is often the preferred treatment for patients with chronic total occlusions, but surgical procedures are undesirably invasive.